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![](https://rs.olm.vn/images/avt/0.png?1311)
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a) (-124) + 24 = -100
b) 37. 78 + 37. 22
= 37 . ( 78 + 22 )
= 37 . 100
= 3700
![](https://rs.olm.vn/images/avt/0.png?1311)
b: \(\dfrac{3}{4}-\dfrac{7}{15}+\dfrac{1}{4}+\dfrac{1}{2022}-\dfrac{8}{15}\)
\(=\left(\dfrac{3}{4}+\dfrac{1}{4}\right)-\left(\dfrac{7}{15}+\dfrac{8}{15}\right)+\dfrac{1}{2022}\)
\(=1-1+\dfrac{1}{2022}=\dfrac{1}{2022}\)
c: \(\dfrac{3}{5}\cdot\dfrac{4}{7}+\dfrac{3}{7}\cdot\dfrac{9}{5}+\dfrac{13}{7}\cdot\dfrac{2}{5}\)
\(=\dfrac{3}{5}\cdot\dfrac{4}{7}+\dfrac{3}{5}\cdot\dfrac{9}{7}+\dfrac{13}{7}\cdot\dfrac{2}{5}\)
\(=\dfrac{3}{5}\left(\dfrac{4}{7}+\dfrac{9}{7}\right)+\dfrac{13}{7}\cdot\dfrac{2}{5}\)
\(=\dfrac{3}{5}\cdot\dfrac{13}{7}+\dfrac{13}{7}\cdot\dfrac{2}{5}\)
\(=\dfrac{13}{7}\left(\dfrac{3}{5}+\dfrac{2}{5}\right)=\dfrac{13}{7}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(=\dfrac{4}{5}\left(\dfrac{-11}{13}+\dfrac{-3}{5}\right)-\dfrac{1}{5}\\ =\dfrac{4}{5}\cdot\dfrac{-94}{65}-\dfrac{1}{5}=\dfrac{-144}{325}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
= 3/7 + 15/26 - 2/13 + 3/7
=3/7 + (15/26 - 2/13)
=3/7 + 4/26
=.......
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\(A=-\dfrac{1}{6}-\left[\dfrac{9}{16}-\dfrac{9}{8}+\dfrac{3}{4}\right]\)
\(=\dfrac{-1}{6}-\dfrac{9-18+12}{16}=\dfrac{-1}{6}-\dfrac{3}{16}\)
\(=\dfrac{-8}{48}-\dfrac{9}{48}=-\dfrac{17}{48}\)
![](https://rs.olm.vn/images/avt/0.png?1311)
\(B=\left(-\dfrac{3}{4}+\dfrac{3}{4}\right)^2+\dfrac{3}{4}\cdot\dfrac{-5}{9}+7^3\)
=-15/36+343
=343-5/12=4111/12
![](https://rs.olm.vn/images/avt/0.png?1311)
\(=64\cdot\dfrac{-1}{8}+100\cdot\dfrac{1}{100}\)
=-8+1
=-7
![](https://rs.olm.vn/images/avt/0.png?1311)
\(\dfrac{\dfrac{5}{3}-\dfrac{5}{7}+\dfrac{5}{9}}{\dfrac{10}{3}-\dfrac{10}{7}+\dfrac{10}{9}}=\dfrac{5\left(\dfrac{1}{3}-\dfrac{1}{7}+\dfrac{1}{9}\right)}{10\left(\dfrac{1}{3}-\dfrac{1}{7}+\dfrac{1}{9}\right)}=\dfrac{1}{2}\)
\(=\dfrac{2^{32}\cdot5^{16}\cdot5^9\cdot2^9\cdot5^6\cdot7^6}{2^{36}\cdot5^{28}\cdot2^5\cdot7^5}=\dfrac{2^{41}\cdot5^{31}\cdot7^6}{2^{41}\cdot5^{28}\cdot7^5}=5^3\cdot7=875\)
\(=\dfrac{2^{32}\cdot5^{16}\cdot2^9\cdot5^9\cdot5^6\cdot7^6}{2^{36}\cdot5^{28}\cdot2^5\cdot7^5}=5^3\cdot7=875\)